For Third Level souls, meditation in the Tachanun prayer enables the coming of the Ruach even while the Nefesh has not been completely rectified.

Now we will explain the differences between Level Two and Level Three [souls].

The Ruach of Level Two, made up of sparks from Cain and Abel, cannot emerge from the depths of the kelipot until the Nefesh is rectified. Therefore, the tikun to the Ruach cannot occur through another person, but only through himself. He must either die, and his Nefesh and Ruach will afterwards come back in another body, as it was explained previously. Or, he can do it by himself with the meditation on the verse "My Nefesh has desired You at night…" (Isaiah 26:9, see Gate of Reincarnations 3:8). After the Nefesh is rectified it will leave, and the Ruach will come by itself to become rectified, as mentioned earlier. It is likewise with the Neshama.

However, the sparks from Level Three have a different ability. Although they cannot achieve all levels in one lifetime, they can achieve tikun using the proper mediations during the Tachanun prayer.

In other words, the souls of level three can grow from Nefesh to Ruach in one lifetime using the proper kavana during the Tachanun prayer. Tachanun is recited most weekdays during the Morning and Afternoon prayers and is a request for forgiveness of sins.

In some communities at this time it is customary to place one's forehead on the arm for a portion of this prayer like one who is distraught and looking for forgiveness.

The actual term the Rav uses in the text is "Nefilat Apayim", which means "falling on the face", and this is a common nomenclature of the prayer, as well. However, since tachanun is a more commonly known terminology these days, that term is used in the translation. He would meditate that he was entering into the lowest realms…to extract from there the remnants of holy sparks…

It was once customary that the person who was praying would fall prostrate on his face during this prayer. At that time he would meditate that he was entering into the lowest realms, the realms of the kelipot, to extract from there the remnants of holy sparks on their way to rectification. In our days this practice is considered too dangerous because the soul of the one who is praying may get caught there. Therefore, at most, in some communities people place their forehead upon their arm; in other communities the prayer is merely recited in a sitting position.

During the "Falling on the Face" prayer, they can meditate that they are extracting their Ruach from the depths of the kelipot. This works even if the Nefesh is not yet fully rectified to ascend in the secret of Mayin Nukvin. (The subject of Mayin Nukvin is also explained in Chapter Three, Section 8.) This meditation is in the verse, "To You, G‑d, I lift up my soul…." (Psalms 25:1)

In the Prayer rite practiced by the Ari, and consequently adopted by all Sephardic Jews and some of the Chasidim, this Psalm is in place of Psalm 6 as the basic text of the Tachanun Prayer. His Ruach is simultaneously being rectified in the body of another person…

His Ruach can then come during his lifetime into the body of another person who is born in combination with the Nefesh of a convert. If he merits it, then it is possible to draw it into his own son born to him.

Therefore, even while the person is rectifying his own Nefesh in his own body, his Ruach is simultaneously being rectified in the body of another person who has the Nefesh of a convert, or, if he merits it, within the body of his own son.

Through the meditation of the "Falling on the Face" prayer, only the Ruach can be withdrawn from the kelipa before the rectification of the Nefesh is completed. This process of drawing out a higher level of soul before the Nefesh has completed its tikun only applies to the level of Ruach. Under no circumstances can the Neshama be drawn from the depths of the kelipot until the Nefesh and the Ruach have been completely rectified, and those people who had the Nefesh and Ruach must die. Afterwards the Neshama can come in a gilgul to achieve tikun.

[Commentary by Shabtai Teicher.]